Free online PPSM to WEBP converter

A PPSM presentation may need conversion when a website, content system, or image viewer accepts WEBP but not PowerPoint files. Conversion rasterizes the slides into images, so the result is not an editable presentation.

What the PPSM format is

PPSM is the PowerPoint Macro-Enabled Show format. It contains presentation slides and can include VBA macros; unlike a PPTM file, opening a PPSM normally starts the slide show. Microsoft PowerPoint creates PPSM files when a presentation is saved as a macro-enabled show. LibreOffice Impress can open PPSM files, though macro behavior may differ from PowerPoint.

What the WEBP format is

WEBP is a raster image format used mainly for web graphics. It supports lossy and lossless compression, transparency, and animation; a slide converted from PPSM is normally a static image. WEBP can make slide images smaller than lossless PNG, but lossy compression may introduce artifacts around text and fine edges.

How to convert PPSM to WEBP

Online on 101convert.com

1. Upload the PPSM file to the converter. Multiple files can be added for batch conversion; the per-file size limit is shown on the page.
2. Before converting, choose the pages and set any needed resolution, quality, image size, max width, max height, auto orient, or strip metadata options.
3. Convert the file, then download the WEBP result.

The conversion runs on the service's server with LibreOffice, then ImageMagick.

Offline with desktop software

Use LibreOffice Impress and ImageMagick, both free and available for Windows, macOS, and Linux. In Impress, open the PPSM file, then choose File → Export As → Export as PDF. Select the desired slide range in the PDF export options. Convert the resulting PDF to one WEBP image per page with ImageMagick:

magick -density 150 presentation.pdf -quality 85 slide-%03d.webp

Replace presentation.pdf with the exported PDF filename. The density setting controls rasterization resolution; the quality value controls lossy WEBP compression. ImageMagick needs PDF-reading support, commonly provided by Ghostscript, and a system security policy may block PDF input.

Quality and limitations

Each selected slide becomes a flattened image: text, shapes, and pictures are no longer individually editable, and slide transitions, animations, and macros are not carried into WEBP. Increase resolution for small text or detailed diagrams; use a higher quality setting to reduce lossy artifacts. Check the resulting images at their intended display size.